Automatic tire pump



June 2, 1925- 1,539,900

H. F. HARVEY AUTOMATI C TIRE PUMP Filed April 2, 1924 All Patented June 2,, 1925.

UNITED STATES nanny r. HARVEY, or rnosrrin, mmvrso'm.

AUTOMATIC TIRE PUMP.

Application filed April 2, 1924. Serial No. 7os,75s.

Toallwhom itmwycmwm:

Be it known that I, HARRY F. HARVEY, a citizen of the United States, residing at Prosper, in the county of Fillmore and State of Minnesota, have invented certain new and useful Improvements in Automatic Tire Pumps, of which the following is a specification.

This invention appertains to automobile appliances and the primary object of the invention is to provide novel means for automatically inflating the pneumatic tire for an automobile, while the automobile is in use, thereby obviating the necessity of infiating .the tires as now generally employed.

A further object of this invention is the provision of a novel pump operatively connected to the pnematic tire of an automobile embodying a plunger for forcing air from the pump into the tire, which is normally held at one end of the pump by a relatively heavy coil spring, and which is adapted to be forced into the pump against the tension of the said spring means by the weight of the automobile upon each revolu-,

tion of the tire, when the same is below its normal air pressure.

A further object of this invention is the provision of an automatic pump for automobile tires embodying a cylinder connected with the tire filling valve casing, a plunger reciprocally mounted within the cylinder anda plunger rod connected to the plunger and extending through the easing into the tire, the rod having connected thereto a helical cushioning spring. the outer convolution of which is normally in engagement with the inner surface of the tread of the tire.

A further object of this invention is the provision of novel means for introducing the air into the pump and novel means for straining the air as the same enters the pump,

A further object of this invention is the provision of novel means for mounting. the plunger engaging spring in the cylinder of pump, whereby the pump will operate, when the air in the tire is below a predeter mined pressure.

A still er object of the invention is in prcvicle animproved automatic air pump above character. which will he dureple and easy to manufacture and one which capt be placed upon the market at a small co With these and other objects in view, the invention consists in the novel construction, arrangement and formation of parts, as will be hereinafter more specifically described, claimed, and illustrated in the accompanying drawings, in which drawings.

Figure l is a side elevation of the improved pump, Figure 2 is a longitudinal section through the improved pump taken on the line 2- 2 of Figure 3 and illustratingthe pump connected with an automobile tire, and

Figure 3 is a top plan view of the improved pump.

Referring to the drawings in detail, wherein similar reference characters designate corresponding parts throughout the several views, the letter-A generally indicates the improved tire pump and B an automobile tire, with which the same can be associated. The automobile tire B is provided with the usual tire filling valve casing 5,

which is connected with the tire B in the of the valve stem casing 5 communicates with the outer end of the cylinder 8. The opposite end of the cylinder 8 is left open and is provided with external threads 10 for receiving a conical cap 11 having an air en trance opening 12 formedthereine in ner surface of the cylinder adjacent to the opening thereof is provided with internal threads 13 for reception of an adjustable dish which is provided with a spring pressed one-way valve 15, which perrnite entrance air into the casing or cylinder, but casing,

prevents the exit of the air irem the a as the same enters into the cylinder so as to prevent the entrance of dust, dirt and the like into the tire a disk of relatively fine wire mesh 16 is placed over the open end of the cylinder and suitable straining material such as raw cotton 17 or the like is placed in between the wire mesh 15 and the cap 11. Formed inte al with the outer surface of the wall of t e and this air way communicates respectively with the op osite ends of .the cylinder by parts 19 'an 20. The part 19 is provided with a valve seat, on which is adapted to normally rest a spring pressed ball valve 21. This sprin pressed a l .valve permits the entrance 0 air into the channel 18 through the outer end thereof but prevents the flow of air into the cfdinder from the tpassageway ed to enga the B is less than 60 at the inner en and way 19.

Reciprocally mounted within the cylinder 8 is a piston 22 and this piston has attached thereto a piston rod 23 which slidably extends through the bore of the j valve stem casing 5 into the tire B. The rod 23 is of a diameter considerably less than the-diameter of the bore of the filling valve stem casing 5 so as to permit the free flow of air th'roug said bore. The inner end of the rod '23 has thereof past sai valve seat attached thereto a helical cushioning spring 24, the convolutions of which gradually decrease in diameter toward said rod. The outer convolution of the spring 24 is adaptthe inner surface of the tire B at the periphery or tread thereof and this convolution is provided with a rubber or like covering 25 so as to prevent injury'to said tire by the s ring. A relative heavy expansion spring 26 is arranged wit in the cylinder 8 and oneend of the .spring engages the piston 22 so'as to normally ur the piston toward the wall 9 of the cylin er and its opposite end is in engagement with the adjustable disk 14. It is obvious that the tension of the spring can be adjusted by moving the plate 14 toward or away from the iston 22. Thus if the normal pressure of t e air in the tire should be 60 pounds the tension of the spring can be adjusted to that tension by moving the pgate 14 inward or outward, as the case may In opera tion of this improved um it can be seen that if the air ressufe in the un s, that the tire will be compressed, ast ewheel turns,'which will of course force the This will compressw the air in the c linde'r and ,force' the same into the channel 18 past the one-way valve 21. In view of the fact that the valve 15 is a one-way valve, the air would be prevented from m ing out of the cylinder. When the point 0 contact of thee ring 24 with the hm p 2-;

cylinder 8 is an air way 18 rod 23 and the pisover the groun it is obvious that the spring 26 will return (the piston ing 5 into the tire. is movement'will also o n the one-way valve 15 and suck air into t e cylinder throu h the capll. This operation is continu until. the air pressure reaches the desired'point, at which time the pressure of the air and the spring 26 become equalized and thus further operation of the pump will be prevented.

From the foregoing description it can be seen that I. have provided an improved means for automatically filling a tire with air during the use thereof.

Changes in details may be made without departing from the spirit or the scope of this invention, but:

What I claim as new is: Y

.1. The combination with an automobile pneumatictire, of an automatic pump-for the tire embodyin 'a cylinder having com-" munication with t e tire, apiston reciprocally mounted within the g cylinder and engaging the said piston for normal] urging the same to one end of the cylin er, means for permitting the entrance venting the exit of air through, said I cylinder, an ex-" pansion spring ofthedesired tension arranged within the of air into the 'cyl; mder from one end thereof andfor 9 a piston rod operatively connected to the plston and extending into the tire, and a ehcal ,cushioning fore g the inner surface or tread of the t1re, as and for the pa specified.

2. The combination wi an automobile pneumatic tire, of a tire valve filling casin connected therewith provided with a longtudmally' extending way therethrough, of

' means for automatically filling the tire with air comprising acylinder operative] connected to said filling valve casing, a unger reciprocally mounted within the c linder, a rod operat vely connected to the limger respring carried by therodciprocally mounted within the filing valve casing and extending into the tire, a helical s rmgconnected to'the e convolutions of the creasin in diameter thereo spring engagin spring toward t e outer end the inner surface of the tire at the trea thereof, a protecting cover formed at the outer convolution of the spring arelatively hea coil spring 'arwithin the cylin er and en sa1 v pl for normally urging the same at one en of the. cylinder, a one-wa valve carried'b one end of thecylinder or permitting t e entrance ofair into the c ,linder, and a wa of the cy flow of air through the way in one direction. 3. The combination with a pneumatic tire outer endof the rod, dually in the outermost diameter of the:

for connecting the opposite ends der together, the way ha a one-way valve therein for e having a tire filling valve casing connected therewith,-of means for fillin the tire with air comprising a pum inclu 'ng a cylinder connectrd with said lling valve casing, a cap carried by the inner end of the pump, straining material fittedin said cap, a piston reciprocally mounted within the c hnder, an expansion sprin arranged wit in the cylinder engaging t e piston for normally holding the piston at one end of the cylinder, a iston rod connected to the piston and extending through the filling valve casing into the tire, a way for operatively connecting the opposite ends of the c linder together, the way having dis ose therein a 15 one-way valve .for controlling the flow of air therethrough, a disk adjustably mounted in the cylinder engaging the spring for adjusting the tension thereof, and a one-way valve carried by said disk.

In testimony whereof I afiix my signature in presence of two witnesses.

' HARRY F. HARVEY.

Witnesses: KARL Cnms'rornnn,

Lnn LANE. 

